Hot-pressing structure of naked battery cell of lithium battery

Abstract

The utility model discloses a hot-pressing structure of a naked battery cell of a lithium battery, and relates to the field of winding and lamination processes and equipment. Comprising an upper template, a lower template, an upper tab hot-pressing block and a lower tab hot-pressing block, the lower template is arranged below the upper template, a roll core or a stacked core is placed on the lower template, one side of the upper template is provided with the upper tab hot-pressing block through a spring or an air cylinder, and one side of the lower template passes through the lower tab hot-pressing block. And positive and negative tabs of a rolled core or a stacked core are arranged between the upper tab hot-pressing block and the lower tab hot-pressing block. According to the utility model, the temperature consistency of the inner and outer layer pole pieces and the isolating membrane of the naked battery cell can be effectively improved, and the effects of defoaming, compounding and shaping are achieved.

Description

Technical Field

[0001] This utility model relates to the field of winding and stacking processes and equipment, specifically to a hot-pressing structure for bare lithium battery cells. Background Technology

[0002] The existing technology in the industry involves the core / stacked core being fed into a hot pressing device via a pull belt. This device has an upper and lower parallel template structure, and the entire set of equipment generally has 3-6 sets of flat pressing mold stations. The template surface is covered with barley paper, etc. (to prevent the template from adhering to the release liner during the hot pressing process) to avoid damage to the core / stacked core. Heating tubes are installed inside the upper and lower templates to bring the surfaces of the two templates to the required process temperature. The lower template is fixed, while the upper template moves up and down by the action of a cylinder and can reach a pressure of 10-30 tons. Through this structure and principle, the electrode sheets and release liner inside the core / stacked core achieve the effects of defoaming, lamination, and shaping.

[0003] Existing technologies have significant drawbacks: after the upper and lower templates reach the required process temperature, the core / stacked core flows into the template. The upper template is pressed down by the sensor, and the hot pressing time varies from 60 to 150 seconds. Actual temperature measurements of the inner and outer electrode layers of the core / stacked core show a large temperature difference, resulting in poor consistency in the defoaming, lamination, and shaping of the semi-finished product, which affects the consistency of the finished product. If the hot pressing time is extended, it will hinder the flow drawing process, reduce production efficiency, and increase manufacturing costs. Utility Model Content

[0004] To address the shortcomings of existing hot-pressing technologies where only the upper and lower templates conduct heat, resulting in uneven temperatures of the inner and outer electrode layers and separator of the bare cell, the purpose of this invention is to provide a hot-pressing structure for bare lithium battery cells that can effectively improve the temperature consistency of the inner and outer electrode layers and separator of the bare cell, achieving the effects of defoaming, bonding, and shaping.

[0005] To achieve the above objectives, this utility model is implemented through the following technical solution: a hot-pressing structure for a bare lithium battery cell, comprising an upper template, a lower template, an upper electrode hot-pressing block, and a lower electrode hot-pressing block. The lower template is provided below the upper template, and a rolled core or stacked core is placed on the lower template. The upper electrode hot-pressing block is provided on one side of the upper template via a spring or cylinder, and the lower electrode hot-pressing block is provided on one side of the lower template. Positive and negative electrode tabs of the rolled core or stacked core are provided between the upper electrode hot-pressing block and the lower electrode hot-pressing block.

[0006] Preferably, brass heating blocks are provided inside the drill holes of both the upper and lower electrode hot pressing blocks.

[0007] Preferably, both the upper and lower templates are equipped with heating devices.

[0008] The beneficial effects of this utility model are as follows:

[0009] This invention can reduce the temperature difference between the inner and outer electrode layers and the separator film of the core / stack, improve product consistency, heat the template and the electrode tabs simultaneously, accelerate the temperature rise rate, shorten the temperature rise time, and improve the efficiency of hot pressing production. Attached Figure Description

[0010] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments;

[0011] Figure 1 This is a schematic diagram of the structure of this utility model. Detailed Implementation

[0012] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0013] Reference Figure 1 The specific embodiment adopts the following technical solution: a hot pressing structure for a bare lithium battery cell, including an upper template 1, a lower template 2, an upper electrode hot pressing block 3 and a lower electrode hot pressing block 4. The lower template 2 is arranged below the upper template 1, and a rolled core or stacked core 5 is placed on the lower template 2. The upper electrode hot pressing block 3 is arranged on one side of the upper template 1 through a spring or cylinder, and the lower electrode hot pressing block 4 is arranged on one side of the lower template 2. Positive and negative electrode tabs 6 of the rolled core or stacked core 5 are arranged between the upper electrode hot pressing block 3 and the lower electrode hot pressing block 4.

[0014] It is worth noting that brass heating blocks 7 are provided in the drill holes of both the upper electrode hot pressing block 3 and the lower electrode hot pressing block 4.

[0015] In addition, heating devices are provided on both the upper template 1 and the lower template 2.

[0016] In this specific embodiment, both the core roll and the stacked core have positive and negative electrode tabs exposed on the body. The copper and aluminum foil has good thermal conductivity. In addition to retaining the existing template heating device, heating and heat conduction of the electrode tabs are added, so that the electrode sheet and the separator film inside the core roll / stack are heated and heated from the inside out at the same time. When the temperature reaches the process standard within the error range, the cylinder is pressurized (this pressure parameter can be verified by DOE) to achieve the effects of defoaming, lamination and shaping.

[0017] This specific implementation uses brass material, drills holes to install heating blocks, and makes them into electrode heating blocks. The heating blocks can extend and retract through springs or cylinders (servo) to contact and press with the electrode tabs, conduct heat to the positive and negative electrode tabs, so that each layer of electrode sheet gradually heats up. Through 3-6 temperature rises and pressurizations, the hot pressing effect is achieved.

[0018] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A hot-pressing structure for a bare lithium battery cell, characterized in that, It includes an upper template (1), a lower template (2), an upper electrode heat pressing block (3) and a lower electrode heat pressing block (4). The lower template (2) is set below the upper template (1). A core or stacked core (5) is placed on the lower template (2). The upper electrode heat pressing block (3) is set on one side of the upper template (1) by a spring or cylinder. The lower electrode heat pressing block (4) is set on one side of the lower template (2). The positive and negative electrode tabs (6) of the core or stacked core (5) are set between the upper electrode heat pressing block (3) and the lower electrode heat pressing block (4).

2. The hot-pressing structure of a bare lithium battery cell according to claim 1, characterized in that, Brass heating blocks (7) are provided in the drill holes of the upper electrode heat pressing block (3) and the lower electrode heat pressing block (4).

3. The hot-pressing structure of a bare lithium battery cell according to claim 1, characterized in that, Heating devices are provided on both the upper template (1) and the lower template (2).

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